If the ger toveled the dishes before conversion, some opinions would say that after the conversion they were a Jew at the time that they toveled them. Similarly, I learned that if a prospective ger bakes a loaf of bread and then finishes their geirus, the bread is pas Yisroel. That aside, nicely sourced answer, thanks.
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yoelNov 6 '12 at 21:34

@yoel I haven't seen the opinion you cite about Pat Akum inside, but it seems to me that that kind of issue would be similar to this one in that the gezera might not apply if there is no chashash of X. If tevillat keilim is a deoraita (which we seem to paskin for metal keilim) then I find it much harder to say something like that will apply.
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Double AA♦Nov 6 '12 at 23:10

1

@yoel, I learned from a rabbi at Ohr Somayach that if a home-brewer converts, any wine he started before he completed his conversion is forbidden to him even if it never left his supervision. But maybe wine is different from bread.
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Monica Cellio♦Nov 7 '12 at 1:32

R' Usher Weiss shlita (Minchas Osher) argues that he doesn't have to, based on the Chazon Ish's principle (Shvi'is 7) that if there's a halacha that comes up all the time and is not a fringe case, and nobody (mishna, gemoro, rishonim, poskim) mentions it, that is an indication that there is no such halacha. This is such a case, since it's relevant every time someone converts and nobody in the past has mentioned it until 50 years ago.

The shiur (Hebrew) is here: click on the one from תשע"א and see from 30 minutes on.

Does he have a makor for this? What is the makor of the Chazzon Ish? Since you nicely pointed out where it is I'll listen to hear. However if you'd like to add a comment or edit your answer and write in his exact makor I think many would appreciate it!
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YehoshuaNov 7 '12 at 10:51

@Yehoshua If I have time I'll listen through again and do that. Feel free to edit the answer yourself if you get there first. I think applying the chazon ish to this question is his own svara, he's certainly on a level to argue with R' Wosner (he does mention the opinions quoted in DoubleAA's answer)
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limosNov 7 '12 at 10:58

I don't understand your proof. Maybe it was so obvious that they have to tovel them that no one mentioned it. In fact, that was my first intuition upon reading the question: duh they have to tovel them!
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Double AA♦Nov 7 '12 at 17:36